My answer, in short, is never. But what I find really interesting is that you even had this question. For me the idea itself that a picture can expire is totally strange. Maybe it is the generation gap and I am missing something. In my book the essence of photography is preserving moments of the past and I could never value them depending on how old they are. But I can get that everything is moving faster nowadays and younger people are overflowed with pictures that tend to consider as disposable. After 6 years here, I believe that hive isn't like that. Old stories are welcome as well as old pictures, if they haven't been posted before. I do state though at the end of my posts if it is old material and when I created it.

Cheers!